Typically, residential and commercial sinks include an outer flange that rests upon the top surface of a counter. A fastening structure is used to attach the sink to the countertop. Various types of fastening structures are available.
One such system is seen in FIG. 18. In this system, fasteners are inserted into a sink bracket by an installer. This is generally a 2-stage operation. The claw and the sink bolt are free to move and rotate. This makes it difficult for the sink to pass through a cutout in the countertop, and also requires both hands to tighten the fastener when installing a sink to the countertop. Generally, one hand is required to hold the fastener and the other to drive the bolt.